ISO 3166-2:CH is the entry for Switzerland in ISO 3166-2, part of the ISO 3166 standard published by the International Organization for Standardization (ISO), which defines codes for the names of the principal subdivisions (e.g., provinces or states) of all countries coded in ISO 3166-1.
The abbreviation is derived from Latin name for Switzerland, Confoederatio Helvetica ("Helvetic Confederation").
Currently for Switzerland, ISO 3166-2 codes are defined for 26 cantons.
Each code consists of two parts, separated by a hyphen. The first part is CH, the ISO 3166-1 alpha-2 code of Switzerland. The second part is two letters, currently used in vehicle registration plates.